gh-114123: Migrate docstring from _csv to csv (#114124)

Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>
Co-authored-by: Éric <merwok@netwok.org>

Lib/csv.py

@@ -1,28 +1,90 @@
 
-"""
-csv.py - read/write/investigate CSV files
+r"""
+CSV parsing and writing.
+
+This module provides classes that assist in the reading and writing
+of Comma Separated Value (CSV) files, and implements the interface
+described by PEP 305.  Although many CSV files are simple to parse,
+the format is not formally defined by a stable specification and
+is subtle enough that parsing lines of a CSV file with something
+like line.split(",") is bound to fail.  The module supports three
+basic APIs: reading, writing, and registration of dialects.
+
+
+DIALECT REGISTRATION:
+
+Readers and writers support a dialect argument, which is a convenient
+handle on a group of settings.  When the dialect argument is a string,
+it identifies one of the dialects previously registered with the module.
+If it is a class or instance, the attributes of the argument are used as
+the settings for the reader or writer:
+
+    class excel:
+        delimiter = ','
+        quotechar = '"'
+        escapechar = None
+        doublequote = True
+        skipinitialspace = False
+        lineterminator = '\r\n'
+        quoting = QUOTE_MINIMAL
+
+SETTINGS:
+
+    * quotechar - specifies a one-character string to use as the
+        quoting character.  It defaults to '"'.
+    * delimiter - specifies a one-character string to use as the
+        field separator.  It defaults to ','.
+    * skipinitialspace - specifies how to interpret spaces which
+        immediately follow a delimiter.  It defaults to False, which
+        means that spaces immediately following a delimiter is part
+        of the following field.
+    * lineterminator - specifies the character sequence which should
+        terminate rows.
+    * quoting - controls when quotes should be generated by the writer.
+        It can take on any of the following module constants:
+
+        csv.QUOTE_MINIMAL means only when required, for example, when a
+            field contains either the quotechar or the delimiter
+        csv.QUOTE_ALL means that quotes are always placed around fields.
+        csv.QUOTE_NONNUMERIC means that quotes are always placed around
+            fields which do not parse as integers or floating point
+            numbers.
+        csv.QUOTE_STRINGS means that quotes are always placed around
+            fields which are strings.  Note that the Python value None
+            is not a string.
+        csv.QUOTE_NOTNULL means that quotes are only placed around fields
+            that are not the Python value None.
+        csv.QUOTE_NONE means that quotes are never placed around fields.
+    * escapechar - specifies a one-character string used to escape
+        the delimiter when quoting is set to QUOTE_NONE.
+    * doublequote - controls the handling of quotes inside fields.  When
+        True, two consecutive quotes are interpreted as one during read,
+        and when writing, each quote character embedded in the data is
+        written as two quotes
 """
 
 import re
 import types
-from _csv import Error, __version__, writer, reader, register_dialect, \
+from _csv import Error, writer, reader, register_dialect, \
                  unregister_dialect, get_dialect, list_dialects, \
                  field_size_limit, \
                  QUOTE_MINIMAL, QUOTE_ALL, QUOTE_NONNUMERIC, QUOTE_NONE, \
-                 QUOTE_STRINGS, QUOTE_NOTNULL, \
-                 __doc__
+                 QUOTE_STRINGS, QUOTE_NOTNULL
 from _csv import Dialect as _Dialect
 
 from io import StringIO
 
 __all__ = ["QUOTE_MINIMAL", "QUOTE_ALL", "QUOTE_NONNUMERIC", "QUOTE_NONE",
            "QUOTE_STRINGS", "QUOTE_NOTNULL",
-           "Error", "Dialect", "__doc__", "excel", "excel_tab",
+           "Error", "Dialect", "excel", "excel_tab",
            "field_size_limit", "reader", "writer",
            "register_dialect", "get_dialect", "list_dialects", "Sniffer",
-           "unregister_dialect", "__version__", "DictReader", "DictWriter",
+           "unregister_dialect", "DictReader", "DictWriter",
            "unix_dialect"]
 
+__version__ = "1.0"
+
+
 class Dialect:
     """Describe a CSV dialect.